The background description provided herein is for the purpose of generally presenting the context of the disclosure. Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Semiconductor memory may be classified as non-volatile memory or volatile memory. A non-volatile memory, e.g., NAND flash memory, may store and retain information even when the non-volatile memory is not connected to a power source. NAND flash memory, or simply NAND memory, or a NAND memory system, may be included in a storage device to store data. Bits may be stored into cells, or memory cells, of a NAND memory, which may be made of floating-gate transistors. A single level NAND memory may include single level cells (SLC) to store one bit data per cell. Alternatively, a multi-level NAND memory may include multi-level cells (MLC) or three level cells (TLC) to store multiple bits data per cell, e.g., two bits, three bits, or more. For an electronic system using a multi-level NAND memory, the time for the electronic system to program multiple bits into the multi-level NAND memory may vary greatly when programmed in multiple passes. For example, an electronic system using a TLC NAND memory may program multiple bits into the TLC NAND memory in multiple passes. Programming data into a TLC NAND memory in a first pass by an electronic system may be much faster, e.g., almost ten times faster, than programming data in the second pass by the electronic system. The time differences between programming of multiple bits in different passes by an electronic system can cause performance deviation of the electronic system using the NAND memory.